The Nai-Form (ない形): Plain Negative of Japanese Verbs

The nai-form (ない形) is the plain-style non-past negative of a Japanese verb. It covers "don't," "doesn't," and "won't" in everyday speech, diaries, novels, and modifying clauses.¹² It is built on the verb's 未然形 (mizenkei, irrealis base) and serves as the launchpad for ないで, なければ, なきゃ, ないように, and most negative grammar a learner meets after N5.¹³⁴

Overview

What the nai-form is

The nai-form is a verb's 未然形 (irrealis base) followed by the negative auxiliary ない.¹³⁴ For ichidan verbs, the irrealis is the bare stem. For godan verbs, it shifts the final u-row kana to the a-row column. For the two irregulars する and 来る, it is supplied lexically as し- and こ-.⁴⁵

ない itself is morphologically an i-adjective. It therefore takes the full i-adjective paradigm: なかった, なくて, なければ, なく.⁶⁷⁸ That one fact controls everything after the basic conjugation in this article.

肉にくを食たべない。⁹
"I don't eat meat."

知しらない人ひと。⁹
"A person I don't know."

Register and where it fits

ない is the plain-style verbal negation. It sits opposite polite-style ません on the 丁寧体 / 普通体 axis.¹⁰¹¹ Plain style is the default inside the speaker's in-group, in diary and internal-monologue prose, and inside almost every subordinate clause regardless of the outer sentence's politeness.¹¹¹²

Corpus frequency in the BCCWJ shows ない and なかった dominating newspapers, academic writing, fiction narration, and most blog prose; ません and ませんでした dominate instruction manuals, customer-facing service text, and public announcements.¹³¹²

明日あしたは学校がっこうに行いかない。²
"I'm not going to school tomorrow."

Plain form is the default for written Japanese

Beginners often picture ます as the "normal" form and ない as a casual alternative. In running prose (novels, news, essays), the picture flips: 普通体 is the default, ない is the unmarked negation, and ません appears mostly in dialogue or service-register passages.¹³¹²

Historical anchor: the 未然形 (mizenkei / irrealis base)

The 未然形 is the first of the six 活用形 (conjugation-form) slots in school grammar (学校文法): 未然形, 連用形, 終止形, 連体形, 仮定形, 命令形.⁴ The name decomposes as 未 ("not yet") + 然 ("so") + 形 ("form"), literally "the not-yet-so form." Japanese Wikipedia glosses the label as "まだそうではないという意味" ("meaning that it is not yet so").⁴

In modern Japanese, several auxiliaries attach to the 未然形: ない (plain negative), ぬ and ん (classical-residue negative), ず (literary negative), れる and られる (passive and potential), せる and させる (causative), う and よう (volitional), and まい (negative volitional).⁴¹⁴

The a-row shift in the godan column is therefore not a rule attached only to ない. It is the shape the 未然形 already has; ない is one of several suffixes that select this slot.⁴⁵

Formation rules

Ichidan (一段) verbs: drop る, add ない

Remove the final る and attach ない directly.¹⁵⁹ The ichidan 未然形 is the dictionary form minus る. It is identical in shape to the 連用形 used for ます.³⁵

Worked: 食べる → 食べない, 見る → 見ない, 起きる → 起きない, 寝る → 寝ない, 教える → 教えない, 始める → 始めない.²¹⁵

朝あさご飯はんを食たべない。²
"I don't eat breakfast."

今日きょうは出でかけない。¹⁵
"I'm not going out today."

何なにも見みえない。¹
"I can't see anything."

Godan (五段) verbs: shift the final u-row kana to its a-row partner, add ない

The dictionary form's final u-row kana shifts to the same column's a-row kana (the 未然形). Then ない attaches to that base.¹⁴⁵ The column-by-column mapping covers every godan ending.

Dictionary ending	未然形 (a-row)	Nai-form
く	か	書かない (kakanai)
ぐ	が	泳がない (oyoganai)
す	さ	話さない (hanasanai)
つ	た	待たない (matanai)
ぬ	な	死なない (shinanai)
ぶ	ば	遊ばない (asobanai)
む	ま	読まない (yomanai)
る (godan)	ら	走らない (hashiranai)
う	わ	買わない (kawanai)

The う row is the only ending whose a-row partner is not the visually expected あ. The next subsection explains why.⁵¹⁴

図書館としょかんで本ほんを読よまない。¹⁵
"I don't read books at the library."

駅えきで友達ともだちを待またない。¹⁵
"I won't wait for my friend at the station."

子こどもはまだ字じを書かかない。²
"The child doesn't write characters yet."

The う-ending exception: う becomes わ, not あ

U-ending godan verbs take 〜わない, not the expected 〜あない.⁵⁹ Worked: 買う → 買わない, 会う → 会わない, 言う → 言わない, 使う → 使わない, 洗う → 洗わない.⁵¹⁶

The exception is regular once you see the history. The verb root historically ended in a consonant -w- (older -f-, earlier Old Japanese -p-). That consonant is "normally suppressed, but surfaces in the negative form, as seen in 買わない (kawanai)."¹⁴ The English Wikipedia conjugation entry frames the surface form as "a leftover from past sound changes, an artifact preserved from the archaic Japanese -fu from -pu verbs."⁵¹⁷

In synchronic terms (describing the modern system), the godan u-verb root ends in -w-. That -w- only appears before -a-, exactly the environment created by the 未然形.¹⁴ Modern 現代仮名遣い writes the surviving form as わ.¹⁸¹⁷

妹いもうとは野菜やさいを買かわない。¹⁶
"My little sister doesn't buy vegetables."

彼かれは本当ほんとうのことを言いわない。¹
"He doesn't tell the truth."

もう誰だれにも会あわない。²
"I won't meet anyone anymore."

Irregular: する → しない, 来る → こない

する's 未然形 is し-, so the plain negative is しない.¹⁵ 来る's 未然形 is こ-, so the plain negative is こない, even though the dictionary form 来る is read くる.⁵¹⁹

The kanji 来 takes three different readings across the paradigm. 来る is くる in the 終止形 and 連体形; 来ない is こない in the 未然形; 来ます is きます in the 連用形.³⁵¹⁹ One kanji has three readings, all driven by the stem.

する-compounds (a Sino-Japanese noun followed by する) follow する: 勉強する → 勉強しない, 電話する → 電話しない, 結婚する → 結婚しない, 運動する → 運動しない.²¹⁵

今晩こんばんは勉強べんきょうしない。²
"I'm not going to study tonight."

田中たなかさんはまだ来こない。¹⁵
"Mr. Tanaka still isn't coming."

後あとで電話でんわしない？¹⁵
"Want to call later?"

The ある exception: a class shift, not a typo

The existential verb ある has a regular 未然形 あら-, but the expected あらない does not exist in modern standard Japanese. The negative is simply ない.¹⁹²⁰

Wiktionary's ある entry lists the negative as ない, with あらぬ and あらん flagged as classical or literary alternates.¹⁹ The everyday spoken and written form is the suppletive ない.

The structural reason is that the ない that fills ある's negative slot is the i-adjective ない ("non-existent"), not the auxiliary ない.⁶⁷⁸ Japanese Wikipedia's 形容詞 entry states this directly: "存在しないことを表す「ない」も形容詞である" ("the ない that expresses non-existence is also an adjective").⁷

Two ない, one surface form

Historically, the two ない forms (the i-adjective "non-existent" and the verbal-negation auxiliary) have separate etymological lines. The auxiliary is an Eastern-dialect form first attested in late Muromachi; the i-adjective is older. Wiktionary notes that the two "may derive ultimately from ancient copula or stative verb ぬ" and "have mostly converged in modern usage."⁸

The practical consequence is that the negative of ある is morphologically a different word (an i-adjective), not a conjugated form of ある. The affirmative paradigm of ある is itself regular (ある, あった, あれば, あって).²⁰¹⁹

時間じかんがない。¹⁹
"There's no time."

お金かねが足たりない。¹⁶
"There isn't enough money."

教室きょうしつに先生せんせいがいない。²
"The teacher isn't in the classroom."

The animate counterpart いる takes the regular auxiliary ない attached to its 未然形 い-, not the suppletive form. Only ある is irregular here.²⁰

Past tense: なかった

Why なかった works: ない conjugates like an i-adjective

ない inflects like any other i-adjective: 未然形 なかろ, 連用形 なかっ and なく, 終止形 ない, 連体形 ない, 仮定形 なけれ.⁶⁷

The past form is the 連用形 なかっ + the past marker た, exactly parallel to 高い → 高かっ + た = 高かった.⁷⁸ One inflection rule covers both classes. Wikipedia's Japanese-grammar entry puts it directly: "Adjectives (i-adjectives) inflect identically to the negative form of verbs, which end in na-i (ない). Compare tabe-na-i → tabe-na-katta and atsu-i → atsu-katta."⁵

Worked examples across classes

Class	Plain non-past	Plain past
Ichidan	食べない	食べなかった
Godan (く)	書かない	書かなかった
Godan (む)	読まない	読まなかった
Godan (う → わ)	買わない	買わなかった
する	しない	しなかった
来る	こない	こなかった
ある	ない	なかった

昨日きのうは何なにも食たべなかった。²
"I didn't eat anything yesterday."

先週せんしゅうは学校がっこうへ行いかなかった。¹⁵
"I didn't go to school last week."

田中たなかさんは来こなかった。²
"Mr. Tanaka didn't come."

時間じかんがなかった。¹⁹
"There was no time."

Negative te-form: なくて vs ないで

Both forms come from the same ない, but they split by function.¹²¹

なくて is the 連用形 なく of the i-adjective ない plus the connective て. It joins clauses by reason, cause, or state: "not X, and …" or "because not X."¹²¹

ないで is ない plus the connective particle で. It joins clauses by manner ("doing Y without doing X") and is the only form usable in negative requests of the form 〜ないでください "please don't."¹²¹

Full coverage of the split is its own topic. At N5, the practical takeaway is the function split: ないで is the request and manner form, and なくて is the reason and state connective.

朝あさご飯はんを食たべないで学校がっこうへ行いった。¹
"I went to school without eating breakfast."

時間じかんがなくて行いけなかった。¹
"I couldn't go because there was no time."

ここで写真しゃしんを撮とらないでください。¹⁵
"Please don't take photos here."

Nuance and usage contexts

Plain-style speech and writing

ない is the default verbal negation in diaries, internal monologue, novels, friend and family conversation, and much journalistic and academic prose (which run in 普通体 throughout).¹¹¹² BCCWJ frequency data confirms that ない dominates fiction narration and editorial writing, while ません dominates customer-facing service language and instruction manuals.¹³¹²

今日きょうは何なにもしたくない。²
"I don't want to do anything today."

Subordinate clauses force plain form

Relative clauses, embedded quotes with と思う or と言う, and conditional antecedents take the plain form (including the nai-form). This is true whether the outer sentence ends in です / ます or in plain form.¹¹¹⁰ Even in a thoroughly polite-style passage, the verb inside a modifier almost always appears in plain form.¹¹

知しらない人ひとと話はなします。¹⁰
"I talk with people I don't know."

In that sentence the relative clause 知らない is plain while the main verb 話します is polite. The same logic applies to embedded thoughts.

来こないと思おもいます。¹⁵
"I don't think he'll come."

The quoted clause 来ない is plain; the outer 思います is polite.

Softening and sentence-final ない

Sentence-final ない with falling intonation is a flat negative. With rising intonation, it commonly functions as a tag, invitation, or confirmation rather than a literal denial.¹⁰¹¹ The same surface form covers "X doesn't" and "Won't you X?" depending on prosody and context.¹⁰

一緒いっしょに行いかない？²
"Want to go together?"

Negative questions and confirmation

〜ない？ in casual speech and 〜ないですか in semi-polite speech serve as invitations or confirmation requests, paralleling polite 〜ませんか.¹⁰¹¹ The plain 〜ない？ form is the everyday peer-register choice. 〜ませんか is the default with strangers, customers, and teachers.¹⁰

ちょっと手伝てつだわない？¹⁰
"Want to help out a bit?"

The nai-form as a launchpad

ないで: "without doing" and negative requests

ないで is ない + で, with two main jobs. As a manner connective, it expresses "doing Y without doing X." As a request frame, it produces 〜ないでください "please don't X."¹¹⁵²¹ Worked: 食べないで, 行かないで, 言わないで, 来ないで, 心配しないで.¹⁵

心配しんぱいしないでください。¹⁵
"Please don't worry."

なければ / なきゃ: obligation and conditionals

なければ is the 仮定形 なけれ + the conditional particle ば. It forms the antecedent of conditional obligation: 〜なければならない or 〜なければいけない "must do."¹¹⁰ なきゃ is the casual contraction of なければ. The dropped ならない or いけない is recoverable from context.¹¹⁰

Worked: 行かなければならない → 行かなきゃ; 食べなければいけない → 食べなきゃ.¹⁰

明日あしたは早はやく起おきなければなりません。²
"I have to get up early tomorrow."

もう行いかなきゃ。¹⁰
"I've got to go now."

なさい and negative imperatives

なさい does not attach to the nai-form

〜なさい is a gentle imperative, but it attaches to the 連用形 (masu-stem), not to the nai-form: 食べなさい (not 食べないなさい), 書きなさい (not 書かないなさい).¹¹⁵ The shared な-syllable in ない (a 未然形 attachment) and なさい (a 連用形 attachment) often confuses beginners.¹¹⁰

Negative imperatives use 〜ないで or 〜ないでください. They can also use the blunt 〜な attached to the dictionary form: 行くな "don't go."¹¹⁵

早はやく食たべなさい。¹⁵
"Eat quickly."

In that sentence なさい attaches to the 連用形 食べ-, not to 食べない.

なくては, なくても, ないように

These three constructions all branch off the i-adjective inflection of ない. They round out the forms an N5 learner will meet next.¹¹⁰

Construction	Function	Worked example
なくては	Obligation antecedent	食べなくては "have to eat"
なくちゃ	Casual contraction	食べなくちゃ "have to eat"
なくても	Concessive	食べなくても "even if not eating"
ないように	Purpose / negative aim	風邪をひかないように "so as not to catch a cold"

風邪かぜをひかないように気きをつけてください。¹⁵
"Please be careful not to catch a cold."

Good to know

Applying the a-row rule to う-verbs and producing 〜あない

A learner who has just internalised "shift the last kana to the a-row" may reach for 買あない when forming the negative of 買う. The correct form is 買わない:

妹いもうとは野菜やさいを買かわない。¹⁶
"My little sister doesn't buy vegetables."

The u-verb root historically ends in -w- (from older -f- and earlier -p-). That consonant surfaces before the -a- of the 未然形 as わ.⁵¹⁴¹⁷ The "shift to a-row" rule still holds; the column for う just lands on わ rather than あ.

Treating ある's negative as あらない

Learners with a strong grip on the godan rule sometimes produce 教室に先生があらない. The correct form replaces ある entirely with the i-adjective ない:

教室きょうしつに椅子いすがない。¹⁹
"There are no chairs in the classroom."

ある has a regular 未然形 あら-, but the negative slot is filled suppletively by the i-adjective ない.⁶⁷¹⁹ あらぬ and あらん survive only in literary or archaic contexts. Modern standard Japanese uses ない. For animate referents, the regular pattern returns: いる → いない.

Attaching ない to the 連用形 instead of the 未然形

A learner who memorised the masu-form first ("u → i + ます") may re-apply that shift under ない and produce 書きない. The correct form attaches ない to the 未然形 書か-:

子こどもはまだ字じを書かかない。²
"The child doesn't write characters yet."

ない selects the 未然形, not the 連用形. The 連用形 hosts ます, たい, なさい, and ながら. The 未然形 hosts ない, ぬ, ず, れる, せる, う, and よう.¹³⁴

Treating 来 as くる across the paradigm

The kanji 来 takes three readings across the conjugation: くる in the dictionary form, き- in the 連用形, and こ- in the 未然形.³⁵¹⁹ A learner who carries the dictionary reading into the negative may read 来ない as くない. The correct reading is こない:

田中たなかさんはまだ来こない。¹⁵
"Mr. Tanaka still isn't coming."

Forming the past plain negative with 〜た on a verb stem

Learners who learn 食べた before 食べなかった sometimes produce 食べないた by adding the verbal past marker directly to ない. The correct form runs through the i-adjective past:

昨日きのうは何なにも食たべなかった。²
"I didn't eat anything yesterday."

ない is an i-adjective, so the past is the i-adjective 連用形 なかっ + た, parallel to 高い → 高かった.⁶⁷⁵ Verbs themselves take 〜た via onbin (sound change), as in 食べた and 書いた. ない blocks that route because it shifts the inflection class.

Confusing verb-negative ない with i-adjective ない

The same surface ない attaches at two different points. With a verb, ない attaches to the 未然形: 食べない, 書かない, しない, こない. With an i-adjective, ない attaches to the く-stem of the adjective: 高くない, 寒くない, おいしくない.²¹ One morpheme has two attachment paths. The rule that picks the path is the part of speech of the host.

ない in a polite-style email

ない is plain-style; the polite equivalent is ません or 〜ないです.¹⁰¹¹ Mixing ない as a sentence-final verb into an otherwise ます-style email is a register slip adult readers notice immediately. For a polite-style document, use this working rule: ない is fine inside modifying clauses (e.g. 知らない人), but the sentence-final verb takes ません.¹¹

The ない auxiliary as a late-Muromachi Eastern form

The modern verbal-negation ない does not descend directly from the classical ず / ぬ paradigm. Wiktionary records it as "first appears in texts from the late Muromachi period as an eastern-dialect term," with "a sizable gap of time between the apparent disappearance of negative auxiliary suffix nafu in the Heian period and the emergence of nai as a suffix in the late Muromachi period."⁸ Standard modern Japanese inherited the Eastern form. The classical ぬ and ず survive in literary registers (知らぬ, 知らず) and in fossilised idioms (やむを得ず "unavoidably").²²⁸

The ある → ない suppletion as a class shift

The ない that negates ある is the i-adjective ない ("non-existent"), not the auxiliary ない.⁶⁷ The "irregular" textbook label hides a cleaner structural fact: in Japanese, the negation of an existential verb has historically lived in the i-adjective class, not in the verbal class. The two ない forms (i-adjective and auxiliary) "have mostly converged in modern usage," but they reached convergence from different etymological lines.⁸

The "a-row + nai, except u → wa" mnemonic

A single jingle covers eight of nine godan columns plus the patch. 書く → 書か → 書かない; 読む → 読ま → 読まない; 買う → 買わ → 買わない.⁵⁹ The mnemonic also makes the 未然形 visible as its own step, preparing learners for later lessons on れる, せる, and よう.

Pitch accent: ない is 頭高 (high-low)

In standard Tokyo Japanese, the auxiliary ない is pronounced high-low; the verb stem keeps its lexical accent. The past form なかった preserves the accent on な-, giving HLLL.¹⁷ Full pitch-accent rules live in their own topic; this note is only a flag.

See also

• Parts of Speech in Japanese: The 10 Classes (品詞)
• The Plain Past た-Form in Japanese: Past, Perfective, and Beyond
• Potential Form: ～られる, ～える, できる
• ～ずに / ～ないで: How to Say "Without Doing" in Japanese
• Pitch Accent for Japanese Verbs and Adjectives: The Binary Class Rule and Conjugation Shifts

References

Footnotes

1. Makino, Seiichi, and Michio Tsutsui. A Dictionary of Basic Japanese Grammar. The Japan Times, 1986. ISBN 978-4-7890-0454-1. Entries on ない (pp. 271–274), the negative-plain paradigm, and the relationship between ない and the 未然形. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶ ↩¹⁷ ↩¹⁸ ↩¹⁹ ↩²⁰ ↩²¹

2. Banno, Eri, Yoko Ikeda, Yutaka Ohno, Chikako Shinagawa, and Kyoko Tokashiki. Genki I: An Integrated Course in Elementary Japanese, 3rd ed. The Japan Times, 2020. ISBN 978-4-7890-1730-5. Lesson 8 (short forms, present plain affirmative and negative); Lesson 9 (past plain forms, including なかった). ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶

3. Tsujimura, Natsuko. An Introduction to Japanese Linguistics, 3rd ed. Wiley-Blackwell, 2014. ISBN 978-1-4051-7058-1. Chapter on verbal morphology; the 未然形 / irrealis analysis; the i-adjective inflection of the negative auxiliary. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

4. ja.wikipedia.org contributors. "未然形." Wikipedia, the Free Encyclopedia (Japanese). https://ja.wikipedia.org/wiki/%E6%9C%AA%E7%84%B6%E5%BD%A2. School-grammar definition of 未然形, the a-row shift for 四段 / 五段 verbs, and the list of auxiliaries that attach to it (ない・ぬ・ず・れる・られる・せる・させる・う・よう・まい). Glosses 未然 as "まだそうではない" ("not yet so"). ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹

5. en.wikipedia.org contributors. "Japanese verb conjugation." Wikipedia, the Free Encyclopedia. https://en.wikipedia.org/wiki/Japanese_verb_conjugation. The mizenkei a-row rule; the う-row exceptional reflex -wa as a residue of archaic -fu / -pu; the irregulars する → しない and 来る → こない; なかった as i-adjective past. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶ ↩¹⁷

6. ja.wikipedia.org contributors. "ない." Wikipedia, the Free Encyclopedia (Japanese). https://ja.wikipedia.org/wiki/%E3%81%AA%E3%81%84. ない as 助動詞 attached to verbal 未然形 vs ない as 形容詞 ("non-existent"); the unified i-adjective inflection paradigm (なかろ・なかっ・なく・ない・ない・なけれ). ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶

7. ja.wikipedia.org contributors. "形容詞." Wikipedia, the Free Encyclopedia (Japanese). https://ja.wikipedia.org/wiki/%E5%BD%A2%E5%AE%B9%E8%A9%9E. The i-adjective paradigm 未然形 かろ / 連用形 かっ・く・う / 終止形 い / 連体形 い / 仮定形 けれ / 命令形 かれ; explicit statement that "存在しないことを表す「ない」も形容詞である." ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸

8. en.wiktionary.org contributors. "ない." Wiktionary, the Free Dictionary. https://en.wiktionary.org/wiki/%E3%81%AA%E3%81%84. Three-etymology entry: ない as i-adjective ("non-existent"), ない as auxiliary (first attested late Muromachi as an Eastern-dialect term), and the proposed common origin in the classical copula / stative ぬ. Inflection cells なく / なかった / なくて / なければ. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷

9. Tofugu. "Japanese Verb Negative ない Form." https://www.tofugu.com/japanese-grammar/verb-negative-nai-form/. Per-group rule statements; the う → わ exception; the ある → ない exception. (limitation): language-learning publisher; used only as a corroborating beginner-grade reference. ↩ ↩² ↩³ ↩⁴ ↩⁵

10. 庵功雄・松岡弘・中西久実子 ほか (Iori, Isao, et al.). 『初級を教える人のための日本語文法ハンドブック』. スリーエーネットワーク, 2000. ISBN 978-4-88319-148-0. Chapter on 文体 (style); treats ない as the plain-style negation marker and as an i-adjective in its inflection paradigm. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵

11. Cook, Haruko Minegishi. "The use of the masu and plain forms in Japanese elementary school classrooms." Language in Society 25, no. 2 (1996): 187–209. Cambridge University Press. The plain (普通体) / polite (丁寧体) axis; plain ない as in-group register and as the default inside modifying clauses. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹

12. Maynard, Senko K. Discourse Modality: Subjectivity, Emotion and Voice in the Japanese Language. John Benjamins, 1993. ISBN 978-90-272-5039-0. The da-style / desu-masu-style distribution across genres; ない and なかった as the unmarked verbal negation in newspapers, academic prose, and fiction narration. ↩ ↩² ↩³ ↩⁴ ↩⁵

13. 国立国語研究所 (NINJAL). 『現代日本語書き言葉均衡コーパス』(BCCWJ). https://clrd.ninjal.ac.jp/bccwj/. Frequency data for the ない paradigm vs ません across written registers (newspapers, magazines, blogs, fiction). ↩ ↩² ↩³

14. en.wikipedia.org contributors. "Japanese godan and ichidan verbs." Wikipedia, the Free Encyclopedia. https://en.wikipedia.org/wiki/Japanese_godan_and_ichidan_verbs. The underlying -w- consonant in う-verb roots that surfaces only before -a (買う → 買わ-); the same irrealis base also feeds -ぬ, -ん, and -ず. ↩ ↩² ↩³ ↩⁴ ↩⁵

15. 3A Corporation. 『みんなの日本語 初級I 第2版』(Minna no Nihongo Shokyū I, 2nd ed.). スリーエーネットワーク, 2012. ISBN 978-4-88319-603-4. Lesson 17 (ない形 / 〜ないでください); Lesson 20 (plain-style sentences); Lesson 21 (plain past, including なかった). ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰ ↩¹¹ ↩¹² ↩¹³ ↩¹⁴ ↩¹⁵ ↩¹⁶ ↩¹⁷ ↩¹⁸

16. PuniPuniJapan. "Negative Plain Form of Verbs." https://www.punipunijapan.com/japanese-nai-form/. Group-by-group conjugation; explicit phrasing of the ある → ない exception. (limitation): language-learning publisher. ↩ ↩² ↩³ ↩⁴

17. Vance, Timothy J. The Sounds of Japanese. Cambridge University Press, 2008. ISBN 978-0-521-61754-3. Modified Hepburn conventions; macron usage for long vowels; the historical -p- > -f- > -w- / zero series behind the modern う-row irrealis. ↩ ↩² ↩³ ↩⁴

18. 文化庁 国語審議会答申. 『現代仮名遣い』. 文部省告示, 1986 (current version). https://www.bunka.go.jp/kokugo_nihongo/sisaku/joho/joho/kijun/naikaku/gendaikana/index.html. Modern kana-orthography reform; underpins the use of わ in 買わない (as opposed to historical かは). ↩

19. en.wiktionary.org contributors. "ある." Wiktionary, the Free Dictionary. https://en.wiktionary.org/wiki/%E3%81%82%E3%82%8B. Suppletive negative pairing: the 未然形 of ある is あら, but the modern negative is ない (not あらない); あらぬ / あらん survive as classical / literary alternates. ↩ ↩² ↩³ ↩⁴ ↩⁵ ↩⁶ ↩⁷ ↩⁸ ↩⁹ ↩¹⁰

20. Martin, Samuel E. A Reference Grammar of Japanese. Yale University Press, 1975 (reprinted University of Hawaiʻi Press, 2003). Sections on the negative paradigm; the suppletive ある / ない relation; the godan irrealis base. ↩ ↩² ↩³

21. Iwasaki, Shoichi. Japanese. Revised edition. John Benjamins, 2013. ISBN 978-90-272-3829-9. Chapter on verbal morphology; explicit treatment of the negative auxiliary ない as inflecting like an i-adjective (なかった, なくて, なければ) and of ないで as the manner / negative-request form distinct from なくて. ↩ ↩² ↩³ ↩⁴ ↩⁵

22. Frellesvig, Bjarke. A History of the Japanese Language. Cambridge University Press, 2010. ISBN 978-0-521-65320-6. Sections on the Old Japanese negative auxiliaries ず / ぬ; the development of the modern ない from the Eastern dialect attested in late Muromachi; the -p- / -f- / -w- sequence behind the godan う-stem irrealis. ↩